The N-terminal domain of KSHV TK is required for both protein localization and morphological change. A schematic diagram of N-terminal KSHV TK truncation clones is shown in panel 1. 143B TK- cells expressing the KSHV TK truncations: KSHV TK (21 to 580) (panel 2), KSHV TK (61 to 580) (panel 3), KSHV TK (81 to 580) (panel 4), KSHV TK (141 to 580) (panel 5), KSHV TK (175 to 580) (panel 6), and KSHV TK (207 to 580) (panel 7). Details of the sequence deletions are displayed under each of the representative panels. Cells counterstained with Hoechst stain are shown in panels 2 to 5; on the right, images of panels 6 to 7 (blue staining) are shown.